Steel BeamInstallers
Basement conversion with steel beams and a steel column on a concrete floor

Basement & cellar steels · Neath

Basement & cellar steels in Neath

Basement & cellar steels for homes in SA10, SA11, designed by a structural engineer.

  • Price fixed in writing once scope is agreed
  • Building control arranged
  • Temporary works and making good included

Free survey in Neath

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  • Free survey visit
  • Engineer's calculations arranged
  • Building control handled
  • Fixed written price once scope is agreed
  • England, Wales, mainland Scotland & NI

About our basement & cellar steels service in Neath

Planning basement & cellar steels in Neath? Our team covers SA10 and SA11 and the streets around them. We also cover the surrounding towns and villages in Neath Port Talbot. You get one written quote for the calculations, approvals, propping, steel and making good.

Underpinning and waterproofing are specialist trades, and we coordinate the steelwork with them rather than replacing them. Our part is the engineer's steel design, building control, temporary propping, and fitting the beams, columns and base plates at the right point in the dig, so the structure is sound before finishes go in.

Things to plan for

  • Temporary works for basements are more involved than for a single opening. The design covers propping the house above, supporting the sides of the excavation, and keeping loads off freshly cast concrete until it has gained strength.
  • Keep the engineer's calculations, waterproofing details, any party wall documents and the completion certificate together. Basement conversions attract questions from buyers' surveyors and lenders, and a complete paper trail makes those questions easier to answer.
  • Cellars often house gas meters, the incoming water main, the electricity supply and old drainage. These are mapped before work starts, gas work must by law be done by a Gas Safe registered engineer, and the electricity network operator may need to move a supply.
  • Basement steel frames often rely on columns because there is nowhere else to land the load. Each column sits on its own foundation or a thickened part of the slab, and its position needs agreeing early so it does not end up in the middle of a room.
  • Victorian and Edwardian cellars often have shallow brick walls, vaulted coal stores extending under the front garden or pavement, and little or no damp protection. The engineer checks whether vaults and walls can stay and what new support they need.

What happens, step by step

  1. Look and measure

    We check the wall, the span you want and what the wall is carrying, and photograph anything the engineer needs to see.

  2. Design and price

    Calculations come back from the engineer and we confirm your fixed written price, line by line.

  3. Building control

    We submit the application or notice to Neath Port Talbot County Borough Council under the Building Regulations as they apply in Wales, before work starts.

  4. Fit, inspect, finish

    The work is propped and the steel installed and packed tight. After inspection the opening is boxed, plastered and left clean.

What do basement & cellar steels cost in Neath?

As a guide, budget £2,300–£5,900 including VAT for basement or cellar steelwork in Neath, based on published UK cost guides adjusted for prices in Wales (-9%).

JobTypical guide rangeWhat it usually covers
Basement or cellar steelwork£2,300–£5,900Beams and columns with pad foundations under the floor above (excavation and waterproofing extra)
Building control fees£230–£590Application fee and inspections under the Welsh building regulations; varies by council or approver
Fire protection to a steel beam£140–£550 per beamFire-rated board boxing or an intumescent coating system as specified
Steel column or post£460–£1,360 per columnColumn supplied and fitted with base and cap plates on a pad foundation

Figures include our approximate regional adjustment for prices in Wales (-9%) and are rounded. How these figures are worked out.

Building rules for Neath

In Wales, structural alterations come under the Building Regulations 2010 as they apply in Wales. Neath Port Talbot County Borough Council handles building control for Neath. For work started or approved from 1 July 2026, the Welsh system uses an application to building control, dutyholders appointed in writing, a commencement notice before work starts and a compliance statement at the end.

Where the steel bears into a wall shared with next door, notice must be served under the Party Wall etc. Act 1996. If your neighbour dissents, surveyors agree how the work is done before it starts.

Building rules in Wales

Basement & cellar steels near Neath

Basement & cellar steels in Neath: your questions

How much do basement & cellar steels cost in Neath?

As a guide, budget £2,300–£5,900 including VAT for basement or cellar steelwork in Neath, based on published UK cost guides adjusted for prices in Wales (-9%). The exact figure depends on the span, what the wall carries, access and the finish, and is fixed in writing once the scope is agreed.

What happens at the survey visit in Neath?

We look at the wall, the floor and ceiling either side and what sits above, measure the opening you want, and note cables, pipes and access for the steel. It usually takes under an hour and there is no charge.

Do I need planning permission to convert a cellar?

Converting an existing cellar into living space usually does not need planning permission if the outside of the house is unchanged, though listed buildings need consent. Digging a new basement, extending under the garden or adding lightwells may need planning permission, and building regulations approval is needed either way.

Do you do the underpinning for a basement?

Underpinning is specialist work, and we coordinate the steelwork with the underpinning contractor rather than carrying it out ourselves. The engineer designs the steel and the underpinning sequence together, so beams, columns and new foundations fit the order in which the walls are deepened.

What paperwork will I get for basement steelwork?

You should end up with the engineer's calculations and drawings, the building control completion certificate, the waterproofing details and, where it applied, the party wall paperwork. Keep them together, as surveyors and solicitors usually ask for them when the property is sold or remortgaged.

Planning to take a wall out?

Book a free survey visit. You get an itemised written quote covering calculations, building control, steel and making good.